Arrays

immarray is imported from List::Objects::WithUtils::Array::Immutable and operates much like an array, except methods that mutate the list are not available; using immutable arrays promotes safer functional patterns.

Inspiration for a few pieces comes from the "classic" (version 0.33) List::MoreUtils. The development versions (0.4+) are going places I don't fully understand, so MoreUtils was dropped from the required dependency chain in Lowu-2.10 and will be reevaluated later. Users with 0.3x versions of List::MoreUtils will see a significant performance boost in performing certain array operations.